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1.
Nature ; 626(7998): 341-346, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38297117

RESUMO

The Middle to Upper Palaeolithic transition in Europe is associated with the regional disappearance of Neanderthals and the spread of Homo sapiens. Late Neanderthals persisted in western Europe several millennia after the occurrence of H. sapiens in eastern Europe1. Local hybridization between the two groups occurred2, but not on all occasions3. Archaeological evidence also indicates the presence of several technocomplexes during this transition, complicating our understanding and the association of behavioural adaptations with specific hominin groups4. One such technocomplex for which the makers are unknown is the Lincombian-Ranisian-Jerzmanowician (LRJ), which has been described in northwestern and central Europe5-8. Here we present the morphological and proteomic taxonomic identification, mitochondrial DNA analysis and direct radiocarbon dating of human remains directly associated with an LRJ assemblage at the site Ilsenhöhle in Ranis (Germany). These human remains are among the earliest directly dated Upper Palaeolithic H. sapiens remains in Eurasia. We show that early H. sapiens associated with the LRJ were present in central and northwestern Europe long before the extinction of late Neanderthals in southwestern Europe. Our results strengthen the notion of a patchwork of distinct human populations and technocomplexes present in Europe during this transitional period.


Assuntos
Migração Humana , Animais , Humanos , Restos Mortais/metabolismo , DNA Antigo/análise , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Europa (Continente) , Extinção Biológica , Fósseis , Alemanha , História Antiga , Homem de Neandertal/classificação , Homem de Neandertal/genética , Homem de Neandertal/metabolismo , Proteômica , Datação Radiométrica , Migração Humana/história , Fatores de Tempo
2.
Nature ; 618(7964): 328-332, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37138083

RESUMO

Artefacts made from stones, bones and teeth are fundamental to our understanding of human subsistence strategies, behaviour and culture in the Pleistocene. Although these resources are plentiful, it is impossible to associate artefacts to specific human individuals1 who can be morphologically or genetically characterized, unless they are found within burials, which are rare in this time period. Thus, our ability to discern the societal roles of Pleistocene individuals based on their biological sex or genetic ancestry is limited2-5. Here we report the development of a non-destructive method for the gradual release of DNA trapped in ancient bone and tooth artefacts. Application of the method to an Upper Palaeolithic deer tooth pendant from Denisova Cave, Russia, resulted in the recovery of ancient human and deer mitochondrial genomes, which allowed us to estimate the age of the pendant at approximately 19,000-25,000 years. Nuclear DNA analysis identifies the presumed maker or wearer of the pendant as a female individual with strong genetic affinities to a group of Ancient North Eurasian individuals who lived around the same time but were previously found only further east in Siberia. Our work redefines how cultural and genetic records can be linked in prehistoric archaeology.


Assuntos
Osso e Ossos , DNA Antigo , Dente , Animais , Feminino , Humanos , Arqueologia/métodos , Osso e Ossos/química , Cervos/genética , DNA Antigo/análise , DNA Antigo/isolamento & purificação , DNA Mitocondrial/análise , DNA Mitocondrial/isolamento & purificação , História Antiga , Sibéria , Dente/química , Cavernas , Federação Russa
3.
Nature ; 592(7853): 253-257, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33828320

RESUMO

Modern humans appeared in Europe by at least 45,000 years ago1-5, but the extent of their interactions with Neanderthals, who disappeared by about 40,000 years ago6, and their relationship to the broader expansion of modern humans outside Africa are poorly understood. Here we present genome-wide data from three individuals dated to between 45,930 and 42,580 years ago from Bacho Kiro Cave, Bulgaria1,2. They are the earliest Late Pleistocene modern humans known to have been recovered in Europe so far, and were found in association with an Initial Upper Palaeolithic artefact assemblage. Unlike two previously studied individuals of similar ages from Romania7 and Siberia8 who did not contribute detectably to later populations, these individuals are more closely related to present-day and ancient populations in East Asia and the Americas than to later west Eurasian populations. This indicates that they belonged to a modern human migration into Europe that was not previously known from the genetic record, and provides evidence that there was at least some continuity between the earliest modern humans in Europe and later people in Eurasia. Moreover, we find that all three individuals had Neanderthal ancestors a few generations back in their family history, confirming that the first European modern humans mixed with Neanderthals and suggesting that such mixing could have been common.


Assuntos
DNA Antigo/análise , Genoma Humano/genética , Homem de Neandertal/genética , Alelos , América/etnologia , Animais , Arqueologia , Bulgária/etnologia , Cavernas , Ásia Oriental/etnologia , Feminino , História Antiga , Humanos , Masculino , Filogenia
4.
Nature ; 581(7808): 299-302, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433609

RESUMO

The Middle to Upper Palaeolithic transition in Europe witnessed the replacement and partial absorption of local Neanderthal populations by Homo sapiens populations of African origin1. However, this process probably varied across regions and its details remain largely unknown. In particular, the duration of chronological overlap between the two groups is much debated, as are the implications of this overlap for the nature of the biological and cultural interactions between Neanderthals and H. sapiens. Here we report the discovery and direct dating of human remains found in association with Initial Upper Palaeolithic artefacts2, from excavations at Bacho Kiro Cave (Bulgaria). Morphological analysis of a tooth and mitochondrial DNA from several hominin bone fragments, identified through proteomic screening, assign these finds to H. sapiens and link the expansion of Initial Upper Palaeolithic technologies with the spread of H. sapiens into the mid-latitudes of Eurasia before 45 thousand years ago3. The excavations yielded a wealth of bone artefacts, including pendants manufactured from cave bear teeth that are reminiscent of those later produced by the last Neanderthals of western Europe4-6. These finds are consistent with models based on the arrival of multiple waves of H. sapiens into Europe coming into contact with declining Neanderthal populations7,8.


Assuntos
Fósseis , Migração Humana/história , Animais , Ásia , Osso e Ossos/metabolismo , Bulgária , Cavernas , DNA Antigo/isolamento & purificação , DNA Mitocondrial/genética , DNA Mitocondrial/isolamento & purificação , Europa (Continente) , História Antiga , Humanos , Homem de Neandertal/genética , Filogenia , Comportamento de Utilização de Ferramentas , Dente/anatomia & histologia , Dente/metabolismo
5.
Radiology ; 312(2): e233039, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39105637

RESUMO

Background Clinical decision making and drug development for fibrostenosing Crohn disease is constrained by a lack of imaging definitions, scoring conventions, and validated end points. Purpose To assess the reliability of MR enterography features to describe Crohn disease strictures and determine correlation with stricture severity. Materials and Methods A retrospective study of patients with symptomatic terminal ileal Crohn disease strictures who underwent MR enterography at tertiary care centers (Cleveland Clinic: September 2013 to November 2020; Mayo Clinic: February 2008 to March 2019) was conducted by using convenience sampling. In the development phase, blinded and trained radiologists independently evaluated 26 MR enterography features from baseline and follow-up examinations performed more than 6 months apart, with no bowel resection performed between examinations. Follow-up examinations closest to 12 months after baseline were selected. Reliability was assessed using the intraclass correlation coefficient (ICC). In the validation phase, after five features were redefined, reliability was re-estimated in an independent convenience sample using baseline examinations. Multivariable linear regression analysis identified features with at least moderate interrater reliability (ICC ≥0.41) that were independently associated with stricture severity. Results Ninety-nine (mean age, 40 years ± 14 [SD]; 50 male) patients were included in the development group and 51 (mean age, 45 years ± 16 [SD]; 35 female) patients were included in the validation group. In the development group, nine features had at least moderate interrater reliability. One additional feature demonstrated moderate reliability in the validation group. Stricture length (ICC = 0.85 [95% CI: 0.75, 0.91] and 0.91 [95% CI: 0.75, 0.96] in development and validation phase, respectively) and maximal associated small bowel dilation (ICC = 0.74 [95% CI: 0.63, 0.80] and 0.73 [95% CI: 0.58, 0.87] in development and validation group, respectively) had the highest interrater reliability. Stricture length, maximal stricture wall thickness, and maximal associated small bowel dilation were independently (regression coefficients, 0.09-3.97; P < .001) associated with stricture severity. Conclusion MR enterography definitions and scoring conventions for reliably assessing features of Crohn disease strictures were developed and validated, and feature correlation with stricture severity was determined. © RSNA, 2024 Supplemental material is available for this article. See also the article by Rieder and Ma et al in this issue. See also the editorial by Galgano and Summerlin in this issue.


Assuntos
Doença de Crohn , Imageamento por Ressonância Magnética , Humanos , Doença de Crohn/diagnóstico por imagem , Feminino , Masculino , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Adulto , Reprodutibilidade dos Testes , Constrição Patológica/diagnóstico por imagem , Pessoa de Meia-Idade
6.
J Theor Biol ; 583: 111769, 2024 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-38423206

RESUMO

Oxygen (O2) regulated pathways modulate B cell activation, migration and proliferation during infection, vaccination, and other diseases. Modeling these pathways in health and disease is critical to understand B cell states and ways to mediate them. To characterize B cells by their activation of O2 regulated pathways we develop pathway specific discrete state models using previously published single-cell RNA-sequencing (scRNA-seq) datasets from isolated B cells. Specifically, Single Cell Boolean Omics Network Invariant-Time Analysis (scBONITA) was used to infer logic gates for known pathway topologies. The simplest inferred set of logic gates that maximized the number of "OR" interactions between genes was used to simulate B cell networks involved in oxygen sensing until they reached steady network states (attractors). By focusing on the attractors that best represented sequenced cells, we identified genes critical in determining pathway specific cellular states that corresponded to diseased and healthy B cell phenotypes. Specifically, we investigate the transendothelial migration, regulation of actin cytoskeleton, HIF1A, and Citrate Cycle pathways. Our analysis revealed attractors that resembled the state of B cell exhaustion in HIV+ patients as well as attractors that promoted anerobic metabolism, angiogenesis, and tumorigenesis in breast cancer patients, which were eliminated after neoadjuvant chemotherapy (NACT). Finally, we investigated the attractors to which the Azimuth-annotated B cells mapped and found that attractors resembling B cells from HIV+ patients encompassed a significantly larger number of atypical memory B cells than HIV- attractors. Meanwhile, attractors resembling B cells from breast cancer patients post NACT encompassed a reduced number of atypical memory B cells compared to pre-NACT attractors.


Assuntos
Neoplasias da Mama , Infecções por HIV , Humanos , Feminino , Algoritmos , Oxigênio , Redes Reguladoras de Genes
7.
Proc Natl Acad Sci U S A ; 118(25)2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34161257

RESUMO

The Initial Upper Paleolithic (IUP) is a crucial lithic assemblage type in the archaeology of southwest Asia because it marks a dramatic shift in hominin populations accompanied by technological changes in material culture. This phase is conventionally divided into two chronocultural phases based on the Boker Tachtit site, central Negev, Israel. While lithic technologies at Boker Tachtit are well defined, showing continuity from one phase to another, the absolute chronology is poorly resolved because the radiocarbon method used had a large uncertainty. Nevertheless, Boker Tachtit is considered to be the origin of the succeeding Early Upper Paleolithic Ahmarian tradition that dates in the Negev to ∼42,000 y ago (42 ka). Here, we provide 14C and optically stimulated luminescence dates obtained from a recent excavation of Boker Tachtit. The new dates show that the early phase at Boker Tachtit, the Emirian, dates to 50 through 49 ka, while the late phase dates to 47.3 ka and ends by 44.3 ka. These results show that the IUP started in the Levant during the final stages of the Late Middle Paleolithic some 50,000 y ago. The later IUP phase in the Negev chronologically overlaps with the Early Upper Paleolithic Ahmarian of the Mediterranean woodland region between 47 and 44 ka. We conclude that Boker Tachtit is the earliest manifestation of the IUP in Eurasia. The study shows that distinguishing the chronology of the IUP from the Late Middle Paleolithic, as well as from the Early Upper Paleolithic, is much more complex than previously thought.

8.
Aging Ment Health ; 28(1): 188-195, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37493469

RESUMO

Objectives: Drawing from the mindfulness framework and the broaden-and-build theory, this study investigates the extent to which mindfulness influences loneliness and whether the relation is mediated by positive and negative affect.Method: Data were collected from 748 retired older adults aged 60 and above in Chengdu, China in 2022. Loneliness and mindfulness were measured by the UCLA loneliness scale and by the short-form version of the Five Facet Mindfulness Questionnaire, while the positive and negative affect was assessed by the International Positive and Negative Affect Schedule.Results: The results of this study show that mindfulness was positively associated with positive affect (ß = 0.37, p<.001), negatively related to negative affect (ß=-0.21, p<.001) and loneliness (ß=-0.13, p<.001), and had an indirect effect on loneliness via positive and negative affect (ß=-0.20, p<.001).Conclusion: The findings suggest that mindfulness could be a positive resource for improving mental health and reducing loneliness among retired older adults in China.


Assuntos
Solidão , Atenção Plena , Humanos , Idoso , Solidão/psicologia , Saúde Mental , Aposentadoria , Inquéritos e Questionários , China
9.
Int J Mol Sci ; 25(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38892466

RESUMO

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults, with few effective treatments. EGFR alterations, including expression of the truncated variant EGFRvIII, are among the most frequent genomic changes in these tumors. EGFRvIII is known to preferentially signal through STAT5 for oncogenic activation in GBM, yet targeting EGFRvIII has yielded limited clinical success to date. In this study, we employed patient-derived xenograft (PDX) models expressing EGFRvIII to determine the key points of therapeutic vulnerability within the EGFRvIII-STAT5 signaling axis in GBM. Our findings reveal that exogenous expression of paralogs STAT5A and STAT5B augments cell proliferation and that inhibition of STAT5 phosphorylation in vivo improves overall survival in combination with temozolomide (TMZ). STAT5 phosphorylation is independent of JAK1 and JAK2 signaling, instead requiring Src family kinase (SFK) activity. Saracatinib, an SFK inhibitor, attenuates phosphorylation of STAT5 and preferentially sensitizes EGFRvIII+ GBM cells to undergo apoptotic cell death relative to wild-type EGFR. Constitutively active STAT5A or STAT5B mitigates saracatinib sensitivity in EGFRvIII+ cells. In vivo, saracatinib treatment decreased survival in mice bearing EGFR WT tumors compared to the control, yet in EGFRvIII+ tumors, treatment with saracatinib in combination with TMZ preferentially improves survival.


Assuntos
Benzodioxóis , Proliferação de Células , Receptores ErbB , Glioblastoma , Quinazolinas , Fator de Transcrição STAT5 , Temozolomida , Fator de Transcrição STAT5/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patologia , Glioblastoma/genética , Humanos , Animais , Quinazolinas/farmacologia , Quinazolinas/uso terapêutico , Benzodioxóis/farmacologia , Benzodioxóis/uso terapêutico , Camundongos , Receptores ErbB/metabolismo , Fosforilação/efeitos dos fármacos , Linhagem Celular Tumoral , Temozolomida/farmacologia , Proliferação de Células/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Transdução de Sinais/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Apoptose/efeitos dos fármacos , Quinases da Família src/metabolismo , Proteínas Supressoras de Tumor
10.
J Proteome Res ; 22(5): 1546-1556, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37000949

RESUMO

Multiomics profiling provides a holistic picture of a condition being examined and captures the complexity of signaling events, beginning from the original cause (environmental or genetic), to downstream functional changes at multiple molecular layers. Pathway enrichment analysis has been used with multiomics data sets to characterize signaling mechanisms. However, technical and biological variability between these layered data limit an integrative computational analyses. We present a Boolean network-based method, multiomics Boolean Omics Network Invariant-Time Analysis (mBONITA), to integrate omics data sets that quantify multiple molecular layers. mBONITA utilizes prior knowledge networks to perform topology-based pathway analysis. In addition, mBONITA identifies genes that are consistently modulated across molecular measurements by combining observed fold-changes and variance, with a measure of node (i.e., gene or protein) influence over signaling, and a measure of the strength of evidence for that gene across data sets. We used mBONITA to integrate multiomics data sets from RAMOS B cells treated with the immunosuppressant drug cyclosporine A under varying O2 tensions to identify pathways involved in hypoxia-mediated chemotaxis. We compare mBONITA's performance with 6 other pathway analysis methods designed for multiomics data and show that mBONITA identifies a set of pathways with evidence of modulation across all omics layers. mBONITA is freely available at https://github.com/Thakar-Lab/mBONITA.


Assuntos
Multiômica , Proteômica , Proteômica/métodos , Transdução de Sinais/genética
11.
J Physiol ; 601(23): 5241-5256, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37878364

RESUMO

The role played by the transient receptor potential vanilloid 1 (TRPV1) channel on the thin fibre afferents evoking the exercise pressor reflex is controversial. To shed light on this controversy, we compared the exercise pressor reflex between newly developed TRPV1+/+ , TRPV1+/- and TRPV1-/- rats. Carotid arterial injection of capsaicin (0.5 µg), evoked significant pressor responses in TRPV1+/+ and TRPV1+/- rats, but not in TRPV1-/- rats. In acutely isolated dorsal root ganglion neurons innervating the gastrocnemius muscles, capsaicin evoked inward currents in neurons isolated from TRPV1+/+ and TRPV1+/- rats but not in neurons isolated from TRPV1-/- rats. The reflex was evoked by stimulating the tibial nerve in decerebrated rats whose femoral artery was either freely perfused or occluded. We found no difference between the reflex in the three groups of rats regardless of the patency of the femoral artery. For example, the peak pressor responses to contraction in TRPV1+/+ , TRPV1+/- and TRPV1-/- rats with patent femoral arteries averaged 17.1 ± 7.2, 18.9 ± 12.4 and 18.4 ± 8.6 mmHg, respectively. Stimulation of the tibial nerve after paralysis with pancuronium had no effect on arterial pressure, findings which indicated that the pressor responses to contraction were not caused by electrical stimulation of afferent tibial nerve axons. We also found that expression levels of acid-sensing ion channel 1 and endoperoxide 4 receptor in the L4 and 5 dorsal root ganglia were not upregulated in the TRPV1-/- rats. We conclude that TRPV1 is not needed to evoke the exercise pressor reflex in rats whose contracting muscles have either a patent or an occluded arterial blood supply. KEY POINTS: A reflex arising in contracting skeletal muscle contributes to the increases in arterial blood pressure, cardiac output and breathing evoked by exercise. The sensory arm of the reflex comprises both mechanoreceptors and metaboreceptors, of which the latter signals that blood flow to exercising muscle is not meeting its metabolic demand. The nature of the channel on the metaboreceptor sensing a mismatch between supply and demand is controversial; some believe that it is the transient receptor potential vanilloid 1 (TRPV1) channel. Using genetically engineered rats in which the TRPV1 channel is rendered non-functional, we have shown that it is not needed to evoke the metaboreflex.


Assuntos
Capsaicina , Canais de Potencial de Receptor Transitório , Animais , Ratos , Pressão Sanguínea , Capsaicina/farmacologia , Artéria Femoral/metabolismo , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Ratos Sprague-Dawley , Reflexo/fisiologia , Canais de Potencial de Receptor Transitório/metabolismo
12.
Bioinformatics ; 38(3): 869-871, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34636843

RESUMO

SUMMARY: WikiPathways is a database of 2979 biological pathways across 31 species created using the drawing software PathVisio. Many of these pathways are not directly usable for network-based topological analyses due to differences in curation styles and drawings. We developed the WikiNetworks package to standardize and construct directed networks by combining geometric information and manual annotations from WikiPathways. WikiNetworks performs significantly better than existing tools. This enables the use of high-quality WikiPathways resource for network-based topological analysis of high-throughput data. AVAILABILITY AND IMPLEMENTATION: WikiNetworks is written in Python3 and is available on github.com/Thakar-Lab/wikinetworks and on PyPI. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Software , Bases de Dados Factuais
13.
PLoS Pathog ; 17(11): e1010016, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34843602

RESUMO

Despite the advent of long-acting anti-retroviral therapy able to control and prevent infection, a preventative vaccine remains a global priority for the elimination of HIV. The moderately protective RV144 vaccine trial suggested functional IgG1 and IgG3 antibodies were a potential correlate of protection, but the RV144-inspired HVTN702 validation trial failed to demonstrate efficacy despite inducing targeted levels of IgG1/IgG3. Alterations in inserts, and antigens, adjuvant, and regimen also resulted in vaccine induced target quantitative levels of the immune correlates, but drove qualitative changes to the humoral immune response, pointing to the urgent need to define the influence of vaccine strategies on shaping antibody quality, not just quantity. Thus, defining how distinct prime/boost approaches tune long-lived functional antibodies represents an important goal in vaccine development. Here, we compared vaccine responses in Phase I and II studies in humans utilizing various combinations of DNA/vector, vector/vector and DNA/protein HIV vaccines. We found that adenoviral vector immunization, compared to pox-viral vectors, resulted in the most potent IgG1 and IgG3 responses, linked to highly functional antibody activity, including assisting NK cell related functions. Minimal differences were observed in the durability of the functional humoral immune response across vaccine regimens, except for antibody dependent phagocytic function, which persisted for longer periods in the DNA/rAd5 and rAd35/rAd5 regimen, likely driven by higher IgG1 levels. Collectively, these findings suggest adenoviral vectors drive superior antibody quality and durability that could inform future clinical vaccine studies. Trial registration: ClinicalTrials.gov NCT00801697, NCT00961883, NCT02207920, NCT00125970, NCT02852005).


Assuntos
Vetores Genéticos/genética , Anticorpos Anti-HIV/imunologia , Antígenos HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Imunidade Humoral , Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/imunologia , Adenoviridae/genética , Adulto , Feminino , Vetores Genéticos/classificação , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/genética , Humanos , Imunoglobulina G/imunologia , Masculino , Desenvolvimento de Vacinas , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia , Adulto Jovem
14.
J Hum Evol ; 183: 103427, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37734121

RESUMO

In the study of Early Pleistocene stone artifacts, researchers have made considerable progress in reconstructing the technical decisions of hominins by examining various aspects of lithic technology, such as reduction sequences, hammer selection, platform preparation, core management, and raw material selection. By comparison, our understanding of the ways in which Early Pleistocene hominins controlled the delivery and application of percussive force during flaking remains limited. In this study, we focus on a key aspect of force delivery in stone knapping, namely the hammerstone striking angle (or the angle of blow), which has been shown to play a significant role in determining the knapping outcome. Using a dataset consists of 12 Early Pleistocene flake assemblages dated from 1.95 Ma to 1.4 Ma, we examined temporal patterns of the hammer striking angle by quantifying the bulb angle, a property of the flake's Hertzian cone that reflects the hammer striking angle used in flake production. We further included a Middle Paleolithic flake assemblage as a point of comparison from a later time period. In the Early Pleistocene dataset, we observed an increased association between the bulb angle and other flake variables related to flake size over time, a pattern similarly found in the Middle Paleolithic assemblage. These findings suggest that, towards the Oldowan-Acheulean transition, hominins began to systematically adjust the hammer striking angle in accordance with platform variables to detach flakes of different sizes more effectively, implying the development of a more comprehensive understanding of the role of the angle of blow in flake formation by ∼1.5 Ma.

15.
AJR Am J Roentgenol ; 221(3): 289-301, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36752369

RESUMO

Neuroendocrine neoplasms (NENs) of the small bowel are typically slow-growing lesions that remain asymptomatic until reaching an advanced stage. Imaging modalities for lesion detection, staging, and follow-up in patients with known or suspected NEN include CT enterography, MR enterography, and PET/CT using a somatostatin receptor analog. FDG PET/CT may have a role in the evaluation of poorly differentiated NENs. Liver MRI, ideally with a hepatocyte-specific contrast agent, should be used in the evaluation of hepatic metastases. Imaging informs decisions regarding both surgical approaches and systematic therapy (specifically, peptide receptor radionuclide therapy). This AJR Expert Panel Narrative Review describes the multimodality imaging features of small-bowel NENs; explores the optimal imaging modalities for their diagnosis, staging, and follow-up; and discusses how imaging may be used to guide therapy.


Assuntos
Neoplasias Intestinais , Tumores Neuroendócrinos , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Intestinais/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Somatostatina , Cintilografia , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/patologia
16.
Ultrasound Obstet Gynecol ; 62(3): 383-390, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37058393

RESUMO

OBJECTIVES: Recently, it was noted that fetuses with open spina bifida (OSB) may have a midline cystic structure evident on ultrasound. Our aims were to determine the prevalence of this cystic structure, shed light on its pathophysiology and investigate the association between its presence and other characteristic brain findings in fetuses with OSB. METHODS: This was a single-center retrospective study of all fetuses with OSB and available cineloop images in the axial plane referred to the Ontario Fetal Centre, Toronto, Canada, between June 2017 and May 2022. Ultrasound and magnetic resonance imaging (MRI) data obtained between 18 + 0 and 25 + 6 weeks were reviewed in search of a midline cystic structure. Pregnancy and lesion characteristics were collected. Transcerebellar diameter (TCD), clivus-supraocciput angle (CSA) and additional brain abnormalities (abnormal cavum septi pellucidi (CSP), abnormal corpus callosum (CC) and periventricular nodular heterotopia (PNH)) were assessed. In cases of in-utero repair, imaging findings were reviewed postoperatively. In cases of termination, neuropathological findings were reviewed, if available. RESULTS: Of 76 fetuses with OSB, 56 (73.7%) had a suprapineal cystic structure on ultrasound. The percentage of agreement between ultrasound and MRI detection was 91.5% (Cohen's kappa coefficient, 0.78 (95% CI, 0.57-0.98)). Brain autopsy in terminated cases revealed a dilatation of the posterior third ventricle, with redundant tela choroidea and arachnoid forming the membranous roof of the third ventricle, anterior and superior to the pineal gland. A cyst wall could not be identified, indicating that the structure was a pseudocyst. The presence of the pseudocyst was associated with a smaller CSA (pseudocyst absent, 62.11 ± 9.60° vs pseudocyst present, 52.71 ± 8.22°; P = 0.04). When the pseudocyst was present, its area was correlated inversely with TCD (r, -0.28 (95% CI, -0.51 to -0.02); P = 0.04). Fetal surgery did not have any impact on the growth rate of the pseudocyst (fetal surgery, 5.07 ± 3.29 mm2 /week vs expectant management, 4.35 ± 3.17 mm2 /week; P = 0.58). The presence of the pseudocyst was not associated with abnormal CSP, CC or presence of PNH. None of the cases with available postnatal follow-up required surgical procedure related to the pseudocyst. CONCLUSIONS: Approximately 75% of all OSB cases have a suprapineal pseudocyst. Its presence is associated with the degree of hindbrain herniation but not with abnormalities of the CSP and CC or presence of PNH. Thus, it should not be regarded as additional brain pathology and should not preclude fetuses from undergoing fetal surgery for OSB. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Espinha Bífida Cística , Gravidez , Feminino , Humanos , Espinha Bífida Cística/diagnóstico por imagem , Estudos Retrospectivos , Idade Gestacional , Encéfalo/diagnóstico por imagem , Feto , Ultrassonografia Pré-Natal/métodos
17.
J Cutan Pathol ; 50(1): 39-42, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35980720

RESUMO

A 29-year-old male presented with a two-week history of a tender lesion on his right thigh. The lesion was a 1.5 cm erythematous nodule with overlying hemorrhagic crust. Histopathologic examination of a biopsy specimen revealed a highly cellular neoplasm with irregular vesicular nuclei, prominent nucleoli, and scattered mitotic figures. The cells within the lesion were rounded, ovoid and spindle shaped cells with perivascular growth. The architecture and staining pattern of the lesion were most consistent with a diagnosis of malignant myopericytoma, an exceedingly rare malignancy.


Assuntos
Miopericitoma , Masculino , Humanos , Adulto , Miopericitoma/patologia
18.
Nature ; 546(7657): 293-296, 2017 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-28593967

RESUMO

The timing and location of the emergence of our species and of associated behavioural changes are crucial for our understanding of human evolution. The earliest fossil attributed to a modern form of Homo sapiens comes from eastern Africa and is approximately 195 thousand years old, therefore the emergence of modern human biology is commonly placed at around 200 thousand years ago. The earliest Middle Stone Age assemblages come from eastern and southern Africa but date much earlier. Here we report the ages, determined by thermoluminescence dating, of fire-heated flint artefacts obtained from new excavations at the Middle Stone Age site of Jebel Irhoud, Morocco, which are directly associated with newly discovered remains of H. sapiens. A weighted average age places these Middle Stone Age artefacts and fossils at 315 ± 34 thousand years ago. Support is obtained through the recalculated uranium series with electron spin resonance date of 286 ± 32 thousand years ago for a tooth from the Irhoud 3 hominin mandible. These ages are also consistent with the faunal and microfaunal assemblages and almost double the previous age estimates for the lower part of the deposits. The north African site of Jebel Irhoud contains one of the earliest directly dated Middle Stone Age assemblages, and its associated human remains are the oldest reported for H. sapiens. The emergence of our species and of the Middle Stone Age appear to be close in time, and these data suggest a larger scale, potentially pan-African, origin for both.


Assuntos
Arqueologia/métodos , Cronologia como Assunto , Fósseis , Hominidae , Filogenia , África/etnologia , Animais , Espectroscopia de Ressonância de Spin Eletrônica , História Antiga , Hominidae/classificação , Humanos , Mandíbula , Marrocos , Dente , Urânio/análise
19.
J Health Commun ; : 1-10, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37908167

RESUMO

Individuals with disabilities experience numerous health disparities compared to their non-disabled peers and face inequities associated with challenges accessing care, stigma, and bias. Health professionals have the opportunity to address health inequities through improved communication, a primary barrier to receiving quality care; however more training is needed. There are limitations to existing tools to measure the skills or self-efficacy of professionals to communicate with individuals with disabilities, and to assess the effectiveness of training programs. The purpose of this study was to develop and validate an instrument to measure health professionals' communication skills and self-efficacy specifically related to working with individuals with disabilities. After a comprehensive review of literature, expert review of proposed scale items, and pilot test, a 19-item survey was administered to 237 healthcare and health and physical education professionals. Construct validity was evaluated by performing an exploratory factor analysis on each subscale and Cronbach's alpha coefficient was used to measure internal consistency. For the skills subscale, Cronbach's α = .919 and for the self-efficacy subscale Cronbach's α = .949 after the removal of one item, resulting in a final 18-item inventory that demonstrates strong validity and reliability.

20.
Artigo em Inglês | MEDLINE | ID: mdl-36804533

RESUMO

Thermal acclimation allows ectotherms to maintain physiological homeostasis while occupying habitats with constantly changing temperatures. This process is especially important in skeletal muscle which powers most movements necessary for life. We aimed to understand how fish skeletal muscle is impacted by acclimatization in the laboratory. To accomplish this, we compared muscle contraction kinetics of four-week lab acclimatized fish (at 20 °C) to fish taken directly from the field when sea surface temperatures were similar to lab treatment temperature (ocean temperature ranged from 17.7 to 19.9 °C in the four weeks prior to collection at 20 °C). To examine these effects, we chose to study tautog (Tautoga onitis) and cunner (Tautogolabrus adspersus) from Long Island Sound. We found that timing of contraction kinetics in cunner and tautog did not differ from the lab acclimatized and field acclimatized groups. However, lab acclimatized cunner produced greater contraction force than fish taken directly from the field. This increased force production allowed lab acclimatized cunner to produce greater power when compared to cunner from the field treatment. Furthermore, laboratory acclimatized cunner did not express any slow myosin heavy chain, suggesting that their muscle had transitioned to mostly fast twitch fibers after being held at a constant temperature in the lab. None of these effects were seen in tautog. In this work we highlight the importance of considering the impacts laboratory conditions have on experimental conditions.


Assuntos
Peixes , Perciformes , Animais , Peixes/fisiologia , Aclimatação/fisiologia , Perciformes/fisiologia , Temperatura , Músculo Esquelético
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